City lighting 'boosts pollution'http://apocadocs.com/s.pl?1292366210
Bright city lights exacerbate air pollution, according to a study by US scientists.
Their research indicates that the glare thrown up into the sky interferes with chemical reactions.
These reactions would normally help clean the air during the night of the fumes emitted by motor cars and factories during the day.
The study was presented at the American Geophysical Union meeting in San Francisco.
All those people going about their business in a city put a complex cocktail of chemicals into the air.
From the tailpipes of cars to the chimneys of factories, it makes for a heady mix of molecules that nature then has to try to clean up. It uses a special form of nitrogen oxide, called the nitrate radical, to break down chemicals that would otherwise go on to form the smog and ozone that can make city air such an irritant on the chest.
This cleansing normally occurs in the hours of darkness because the radical is destroyed by sunlight; it only shows up at night.